Cold water's being poured on the National Party's idea to keep Marsden Point oil refinery in an operational state, in case it's needed in the future.

Shareholders have voted to drastically scale back operations at the Whangārei refinery - and switch to distributing pre-refined fuels.

Refining NZ Chief Executive Naomi James told Mike Hosking National's proposal isn't a realistic option so it's not something the company's exploring.

“You don’t just need the facilities in a state that can be restarted, which would be very costly to maintain, you also need a workforce.”

Naomi James says Refining NZ is looking at parts of the refinery that could be mothballed to reuse for bio-fuel manufacturing in the future.

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